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Electrospinning synthesis of 3D porous NiO nanorods as anode material for lithium-ion batteries

1 Introduction Lithium-ion batteries have recently been widely applied as an important energy source of new energy vehicles. However, commercialized lithiumion battery anode materials [ 1 , 2 ], which are mostly made of carbon materials, have some disadvantages. For example, metallic lithium and carbon have similar electric potentials, which causes precipitation of lithium dendrites resulting in short circuit. In comparison, NiO discharge platform is generally higher than that of graphite [ 3 – 5 ], which can avoid lithium dendrites to some extent and

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Effects of thermal treatment and fluoride ion doping on surface and catalytic properties of NiO–ZrO2 catalysts

procedure, sulfating agent, precipitation procedure [ 21 ], thermal treatment, hydration degree and addition of transition metals as promoters [ 22 , 23 ]. Numerous studies have also been devoted to NiO-based catalysts such as NiO–AlO 3 and NiO–SiO 2 systems which are widely used as catalysts for the oxidative dehydrogenation of ethane to ethylene, NO reduction by CO and CH 4 –CO reforming. The surface properties and the catalytic performance of these catalyst systems have been reported [24–26]. The aim of the present work is to investigate the structural

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Synthesis of NiO nanoparticles by sol-gel technique

Abstract

NiO nanoparticles were fabricated by sol-gel route using ammonium hydroxide and nickel nitrate as precursors. The NiO nanoparticles were calcinated at 400 °C and 1000 °C. The nanoparticles were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), vibrating sample magnetometer (VSM), thermogravimetry analysis/differential thermal analysis (TGA/DTA). The structural properties were evaluated by X-ray diffraction (XRD). XRD confirmed the formation of well-crystallized and high purity NiO phase. The XRD showed that the peaks were sharpened and the crystallite size increased as the calcination temperature increased. The average crystallite size ranged from 12 nm to 20 nm, when calcined at temperatures 400 °C and 1000 °C, respectively. Fourier transform infrared spectroscopy (FT-IR) revealed the chemical composition and confirmed the formation of NiO nanoparticles. The nanoparticles showed paramagnetic behavior.

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A novel photoelectrode of NiO@ZnO nanocomposite prepared by Pechini method coupled with PLD for efficiency enhancement in DSSCs

Abstract

The dye-sensitized solar cells made of NiO@ZnO nanoparticles were synthesized by a novel Pechini route using different NiO molar concentration ratios. The thermal, structural morphological, optical and electrical properties of the prepared samples were investigated using thermal gravimetric analysis and differential scanning calorimetery (TGA/DSC), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), FT-IR and Raman spectroscopy, UV-diffuse reflectance (UV-DRS), photoluminescence (PL) and current-voltage (I-V) measurements. The success of doping process was confirmed by the XRD patterns, which revealed the existence of new peak at 43.2° corresponding to secondary phase NiO. UV spectra exhibited red shifts in NiO doped ZnO NCs and PL spectra showed strong emission band at 355 nm. The doping of ZnO with NiO was intended to enhance the surface defects of ZnO. The current-voltage measurements showed an improvement of the short circuit photocurrent (Jsc) and fill factor (FF) and a decrease in the open circuit voltage (VOC) for dye-sensitized solar cell (DSSC) based on NiO-ZnO NCs. A clear enhancement in efficiency of DSSC from 1.26±0.10 % for pure ZnO to 3.01±0.25 % for NiO-ZnO NCs at the optimum doping with 1.5 mol% of NiO to ZnO (ZN1.5) was observed. The obtained material can be a suitable candidate for photovoltaic applications.

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Magnon and Phonon Excitations in Nanosized NiO

REFERENCES 1. Lee, D. U., Fu, J., Park, M. G., Liu, H., Ghorbani Kashkooli, A., & Chen, Z. (2016). Self-assembled NiO/Ni(OH) 2 nanoflakes as active material for high-power and high-energy hybrid rechargeable battery. Nano Lett. , 16 , 1794–1802. DOI: 10.1021/acs.nanolett.5b04788 2. Browne, M., Nolan, H., Berner, N., Duesberg, G., Colavita, P., & Lyons, M. (2016). Electrochromic nickel oxide films for smart window applications. Int. J. Electrochem. Sci. , 11 , 6636–6647. DOI: 10.20964/2016.08.38 3. Lee, S. G., Lee, S., & Lee, H. I. (2001

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Characterization of NiO–Al2O3 composite and its conductivity in biogas for solid oxide fuel cell

creep resistance compared with the conventional Ni anodes. Further, the presence of Al 2 O 3 may increase the surface area of the NiO accompanied by an increase in the catalytic and chemisorptive activity of NiO. In view of the catalytic activity of NiO–Al 2 O 3 for hydrocarbons, we here propose it as an anode material for hydrocarbon based intermediate temperature solid oxide fuel cells. The nanopowders of NiO and α-Al 2 O 3 were obtained by solution combustion and were mixed physically to get a composite. The benefits of solution combustion are low cost

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Long-term (30 days) toxicity of NiO nanoparticles for adult zebrafish Danio rerio

References Baek YW, An YJ. (2011). Microbial toxicity of metal oxide nanoparticles (CuO, NiO, ZnO, and Sb2O3) to Escherichia coli, Bacillus subtilis, and Streptococcus aureus. Sci Total Environ 409: 1603-1608. Dunnick JK, Elwell MR, Radovsky AE, Benson JM, Hahn FF, Nikula KJ, Barr EB, Hobbs CH. (1995). Comparative carcinogenic eff ects of nickel subsulfi de, nickel oxide, or nickel sulfate hexahydrate chronic exposures in the lung. Cancer Res 55: 5251-5256. Gong N, Shao K, Feng W, Lin Z, Liang C, Sun Y. (2011

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Space Vector Pulse Width Modulation for High-Speed Induction Motor Implemented in Nios II Softcore Processor

-26. Rashidi, B. and Sabahi, M. (2013). High Performance FPGA Based Digital Space Vector PWM Three Phase Voltage Source Inverter. International Journal of Modern Education and Computer Science, 1, pp. 62-71. Xu, Y. and Xiang, M. (2009). Design a new type PWM peripherals in Nios II. In: 2009 WRI World Congress on Computer Science and Information Engineering, Los Angeles, CA, 2009, IEEE, pp. 442-446. Ying-Yu Tzou and Hau-Jean Hsu. (1997). FPGA Realization of Space-Vector PWM Control IC for Three-Phase PWM Inverters. IEEE Transactions on Power

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UV-Vis studies of 800 keV Ar ion irradiated NiO thin films

Abstract

We report the evolution of optical absorption properties of 800 keV Ar ion irradiated NiO thin films through UV-Vis characterization. Our results indicate the existence of both Mott-Hubbard (d → d transition) and charge-transfer (p → d transition) characteristic of NiO. The optical band gap of NiO increases from 3.58 to 3.75 eV when irradiated at the fluence of 5 × 1014 ions cm-2 but it does not show any remarkable variation upon 800 keV Ar ion irradiation at higher fluences. The refractive index and electron polarizability at different ion fluences have been determined from the optical band gap. Both refractive index and electron polarizability follow an opposite trend to that of the energy gap as a function of ion fluence.

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Optimization and characterization of NiO thin films prepared via NSP technique and its P-N junction diode application

Abstract

The present work reports on the optimization of substrate temperature, molar concentration and volume of the solution of nickel oxide (NiO) thin films prepared by nebulizer spray pyrolysis (NSP) technique. NiO films were optimized and characterized by XRD, SEM, EDX, UV-Vis and I-V measurements. Based on XRD analysis, the molar concentration, volume of solution and substrate temperature of the prepared NiO films were optimized as 0.20 M, 5 mL and 450 °C for P-N diode applications. The XRD pattern of the optimized NiO film revealed cubic structure. The surface morphological variations and elemental composition were confirmed by SEM and EDX analysis. The optical properties were studied with UV-Vis spectrophotometer and the minimum band gap value was 3.67 eV for 450 °C substrate temperature. Using J-V characteristics, the diode parameters: ideality factor n and barrier height Φb values of p-NiO/N-Si diode prepared at optimum conditions, i.e. 450 °C, 0.2 M, 5 mL, were evaluated in dark and under illumination.

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